efliciency may be affected by a multitude of factors, it is obvious that the
use of general mean values for estimating food requirements, without
taking into account the actual nutritional state of the fish, may lead to an
erroneous estimation of the food ration. For the values inserted in the
above equations to be meaningful, the effect of the factors mentioned
above should be known and considered.
In this book a discussion on the factors affecting food requirement and
utilization is attempted. Since one must take into account the arguments
discussed above that there is a difference in partial efficienies for
maintenance and growth, these parameters are discussed separately in
Chapters 4 and 5.